SAP report estimates how fast warmth escapes from your home via ventilation, air leakage and the building fabric. Nicola Jones and Paul Rea minimised heat loss by packing plenty of sheep’s wool insulation into their new house, achieving an airtightness figure of 1.78 air changes per hour. Inset: Your SAP report will also take solar gaininto account. Nicola and Paul positioned their house so most of the windows face south, maximising natural warmth from the sun
The Standard Assessment Procedure (SAP) is a methodology that reviews and compares the amount of energy a house will consume when delivering a defined level of comfort and service provision. It’s the most commonly used practice for this purpose because it’s the one that’s approved by the UK government. The technique used to assess your home’s energy performance needs to be government-approved because the results underlie Part L of the Building Regulations, which is the section that deals with conservation of fuel and power in a property.